Load control means for bucket wheel excavators



g 9, 1969 o. E. SEBOLD 3,461,530 I LOAD CONTROL ME EEEEEEEEEEEEEEEEE L E AAAAAAA RS Filed Feb. 14, 1966 2 SheetsSheet 1 IO 36 35 -I7 2| 285 ll INVENTOR.

OTTO E. SEBOLD 2 Win/W? I Q ATTORNEYS Aug. 19, 1969 O. E. SEBOLD 3,

LOAD CONTROL MEANS FOR BUCKET WHEEL EXCAVATORS Filed Feb. '14, 1966 I 2 Sheets-Sheet 2 INVENTOR. OTTO E. SEBOLD ATTORNEYS United States Patent US. Cl. 37-189 1 Claim ABSTRACT on THE DISCLOSURE A device for controlling the type of material admitted to the buckets of a bucket wheel excavator. The load control device according to this invention comprises a blocking means, such as a plate, mounted ahead of each bucket anouth and within a bucket loading zone so that large chunks of material or rock are prevented from entering the bucket mouth.

This invention relates to excavating machinery and, more particularly, to means for controlling the type of material excavated by a bucket wheel excavating machine.

Bucket wheel excavators include an excavating or digging wheel which is mounted for rotation about its axis. The wheel is usually mounted in a vertical plane, although frequently such wheels are canted at a slight angle to the vertical. The digging wheel comprises a drum having a multiplicity of digging buckets mounted about its periphery. Each digging bucket has a mouth opening in the direction of wheel rotation. The wheel drum is commonly (although not necessarily) provided with openings beneath each bucket, which permits the excavated material to drop into the interior of the wheel. A slope sheet may be employed to receive the material within the wheel and to discharge such material onto a conveyor belt which extends from the bucket wheel to another conveyor belt for eventual discharge into a truck.

Frequently the excavated material contains large boulders, rock formations, bands of hard strata, or frozen earth. These solid formations may comprise or form large lumps as they are excavated by the buckets of the rotating wheel. These lumps may be too large to pass through the mouth of the bucket and may become lodged within the bucket mouth, thereby closing the bucket and preventing bucket fill, with resulting loss of output. Frequently these formations are carried over and dropped behind the rotating wheel onto the excavating machine, causing injury to the operator and/or equipment damage. Those hard formations which are suffiicently small to pass through the buckets mouth frequently become lodged in the discharge and/or conveying passages of the bucket wheel excavator, thereby causing clogging of the excavators discharge and conveying passages. Furthermore, such formations may inflict heavy damage to and cause expensive wear of the conveyors. The excavation of such materials, therefore, results in the reduction of output due to down time for removal of obstacles from the excavator, repairs to the excavator, and increased maintenance and operating costs.

The present invention effectively eliminates many of these problems by providing a load control means adjacent to or in the mouth of each bucket to divide the cross sectional opening of each bucket month without substantially reducing the excavating capacity of each bucket. The load control means according to this invention is located within a bucket loading zone adjacent each bucket and from which the bucket may be loaded as the excavating wheel is operated. According to this ice invention, at least a portion of each load control means may be positioned within a bucket loading zone which is bounded by the inner surface of its bucket, a plane tangent to the bucket wheel drum at the intersection of the bucket mouth and the drum, and an envelope traced by the open mouth of each bucket as each bucket is rotated about the digging wheel axis. Preferably, at least a portion of each load control means is positioned within a bucket loading zone which is Ibounde'd by a plane of the bucket mouth opening, by an envelope traced by the open mouth of each bucket as it rotates about the digging wheel axis, and by an envelope traced by a line on the plane of the bucket mouth opening at its intersection with the bucket wheel drum as that plane is pivoted radially outwardly about a line in said plane that is parallel to the wheel axis and located at the outer limit of the bucket mouth.

According to a further aspect of the present invention, the load control means may comprise a flat plate having a minimum profile (an edge) and a maximum profile (a face), which plate is positioned in a load control zone so that the plate presents its minimum profile to a bucket mouth opening.

According to a further aspect of the present invention, a load control means, such as a flat plate may have cutting means, such as saw type teeth, which extend beyond the circle traced by the cutting teeth or cutting lip of each excavating bucket to serve as supplementary cutting means for breaking up large lumps such as slabs, banded strata, or frozen earth layers.

The objects and advantages of the present invention and the method of achieving them will be more fully understood from the following description of the invention and from the accompanying drawings illustrating the same, it being understood that the drawings and specific description of the invention are presented as examples of presently preferred forms of the invention without intending that the invention be considered limited thereto.

Referring to the drawings:

FIG. 1 is a partially schematic, perspective view of the excavating wheel portion of an excavating machine which embodies the present invention;

FIG. 2 is a fragmentary, enlarged elevational view of a portion of the bucket wheel excavator illustrated in FIG. 1; and

FIG. 3 is a sectional view, the plane of the section being indicated by the line 3-3 in FIG. 2.

Referring now to the drawings, the digging wheel portion 10 of an excavating machine is illustrated. The illustrated digging wheel portion 10 is supported by a boom 11 which also supports a conveyor belt 12. The digging wheel portion is driven about its axis in a clockwise direction, as viewed in FIGS. 1 and 2, by driving means (not shown). The excavating wheel portion 10 comprises a drum 13 which includes inner and outer cylinders 14 and 15, respectively. A multiplicity of excavating buckets 16 are removably attached to the outer cylinder 15 of the drum 13. Each excavating bucket 16 comprises a shell 17 having a mouth 18 which is open in the direction of bucket rotation. The shell 17 has a back wall 19 which slopes toward and is removably fixed to the outer cylinder 15 of the drum 13 by bolts 20. Each bucket 16 further includes a bucket lip 21 having extensions 21a which, together with portions of the shell 17, extend through spaced slots 22 provided in the outer cylinder 15.

The extensions 21a, together with portions of the shell 17, are removably fixed to the drum 13 by a pin 23. As may be seen most clearly in FIG. 3, the pin 23 extends through the extensions 21a and portions of the shell 17 and has reduced end portions 24 which project through openings 25 in a pair of annular, side, spacing plates 26.

Each pin 23 is retained by a plate 27 which is bolted to the plate 26 and which surrounds a portion of the reduced end portion 24 of the pin 23.

Each bucket 16 further includes bucket teeth 28 which bite into the material to be excavated.

Portions of the inner and outer drum-forming cylinders 14 and are removed radially inwardly of each bucket 16 to form a discharge opening 29 for each bucket. As excavated material is scooped up by each bucket 16, such material is permitted to fall through the associated opening 29 as it and its opening 29 traverse the upper portion of their circular path.

As may be seen most clearly in FIG. 3, the excavated material falls onto a slope sheet 30 and slides onto the conveyor belt 12. The conveyor belt 12 carries the excavated material to a point remote from the digging location and deposits the excavated material in a truck or onto a second conveyor for ultimate delivery to a truck or desired repository.

In order to excavate material, the bucket wheel must be brought into a position so that the material to be excavated is located in a bucket loading zone (FIG. 2) which, for each bucket, is located generally ahead of the bucket. More specifically, a bucket loading zone comprises a zone bounded by the inner surface 32 of a bucket 16, a plane 33 which is tangent to the drum 13 at the intersection of the bucket mouth 18 and the drum 13, and an envelope 34 traced by the open mouth 18 of each bucket 16 as each bucket is rotated about the axis of the excavating Wheel.

A load control means 35 is provided for each bucket 16 and, as is shown in the drawings, may comprise a fiat plate 36 which is fixed to the back wall 19 of each bucket and projects into the previously defined loading zone of the next trailing bucket.

Preferably, at least a portion of each load control means 35 projects into a more restricted loading zone which is bounded by a plane 37 of the bucket mouth opening 18 by an envelope traced by the open mouth 18 of each bucket as it rotates about the wheel axis and by an envelope 38 which is traced by a line on the plane 37 defined by the intersection of the bucket mouth opening 18 and outer cylinder 15 as the plane 37 is pivoted radially outwardly about a line 39 in that plane which is parallel to the axis of the excavating wheel and located at the outer limit of the bucket mouth. Locating each load control means 35 within the first-defined loading zone, and preferably within the second-defined, more restricted loading zone, screens out large chunks of agglomerated material by partially obstructing the mouth opening 18 to the entrance of such large chunks.

A load control means 35 may be provided with means for precutting the material to be excavated. Such precutting means may comprise one or more teeth (not shown) which may be fixed to a load control means and which serve as supplementary cutting tools for breaking up large lumps, such as slabs, banded strata, or frozen earth layers. The precutting means should extend outwardly to or beyond the circle traced by the uppermost teeth 28 on the bucket opening.

From the foregoing, it will be apparent that the present invention may take numerous different forms without departing from the principles thereof as described and illustrated herein. For example, more than one load control means may be provided in a single loading zone. Therefore, it is to be understood that the scope of the invention is not intended to be limited by details of the embodiments shown and described, except as required by the terms of the appended claim.

What is claimed is:

1. In a bucket wheel excavator having a digging wheel mounted for rotation about its axis and comprising a drum having a multiplicity of digging buckets mounted about its periphery, said digging buckets having mouths opening in the direction of wheel rotation, and means defining openings in said drum radially inwardly of each bucket whereby the excavated material may drop within the interior of the drum, the combination therewith of the improvement comprising load control means associated with each bucket, at least a portion of each load control means being positioned within a loading zone for the associated bucket, each such zone being bounded by the inner surface of the bucket, by an envelope traced by a line on the plane of the bucket mouth opening at its intersection with said drum as the plane is pivoted radially outwardly about a line in said plane that is parallel to the wheel axis and located at the outer limit of the bucket mouth, and by an envelope traced by the open mouth of each bucket as it rotates about the digging 'Wheel axis, each load control means being fixed to the outside surface of a bucket, and wherein each load control means is a fiat plate having a minimum profile and a maximum profile and wherein each plate lies in a plane transverse to said axis.

References Cited UNITED STATES PATENTS 244,400 7/1881 Plumb 37-94 1,113,952 10/1914 Brown 37-94 1,386,987 8/1921 Brown 37-97 2,700,235 l/ 1955 Kolbe.

2,935,801 5/1960 Stewart et a1 37191 X ANTONIO F. GUIDA, Primary Examiner A. E. KOPECKI, Assistant Examiner 

